For practical purposes, think of a chord as three or more
different-pitched notes played or sung simultaneously. Not two.
Consider two notes, whether sounded simultaneously or in
succession, an interval.

Successions
of chords—chord progressions—are the units of harmony. Just as successions of
intervals are the units of melody.

Psychologically,
as discussed in Chapter 3, harmony provides aural “depth” to melody’s height and
rhythm’s length. Harmony has nothing to do with pitch-like “height.” You’ll find
out why later in this chapter.

THE
JIMI
HENDRIX
EXPERIENCE
WITHOUT
JIMI:
WHY MELODY-FREE
HARMONY
DOES
NOT
STAND
ON ITS
OWN

When you play a melody comprised of the notes
that make up a chord, such as C – E – G – E – C, your brain recognizes the
underlying chord because the sequence goes by quickly. But when you play all the
notes of a chord simultaneously, your brain hears a single unified sound—not the individual notes that comprise the
chord.

You
can recognize a tune—a succession of notes—as a piece of music all by itself. No
harmony whatsoever. A national anthem, or “Happy Birthday,” or a bugle call, for
instance.

And
yet, paradoxically, a harmonic progression—a succession of chords without
a tune—does not sound like “complete” music at all. It sounds like the Jimi
Hendrix Experience without Jimi.

Unlike harmony-free melody, melody-free harmony does not
stand on its own.

If you were to play the chords
to “The Star Spangled Banner” without playing or singing the succession of
pitches that forms the tune, no one would recognize it as one of the world’s
most widely-known songs.

On the
other hand, a lone, completely unaccompanied tune is like a movie storyboard—a
sequence of sketches, much like the sequence of panels forming a comic strip.
The storyboard outlines the shot-by-shot sequence of a scene—the essentials of
the “story” for that scene. You can discern what the story is from the
storyboard, but it lacks color, depth, and liveliness.

Chapter 4 discussed the “organizing principle”
that underlies the construction of brain-friendly, “musical”-sounding scales:
use the simple ratios of frequencies of the harmonic series, such as 2:1, 3:2,
and 4:3, to define the notes. When you do that, you get Pythagorean scales,
including the scales of the diatonic order.

Is there a similar organizing principle that applies the construction
of brain-friendly, musical-sounding chords?

Yes there is.

But
with chords, it’s a matter of “organizing,” so to speak, the scale degrees
associated with the overtones of the harmonic series, instead of the overtones
themselves.

Recall
that the term “scale degree” refers to the designation of the notes of a major
or minor diatonic scale using numbers: 1, 2, 3, 4, 5, 6, 7, and 1 (8), where 1
is the tonic note of the scale, 7 is the leading tone, and so on. It turns out
that most of the strong overtones—1st, 2nd, 3rd, 4th, 5th, 7th, and 9th—of a
given fundamental tone (scale degree 1) correspond to the pitches associated
with scale degrees 1, 3, and 5 of the major diatonic scale (Table 33 below). And
when you play these three scale degrees—1, 3, and 5— simultaneously, you get a
chord.

TABLE 33
Fundamental and First 9 Overtones of the Tone “C”

When
you play the notes C, E, and G (scale degrees 1, 3, and 5) simultaneously on
your guitar or piano, you hear a beautiful harmonic sound. It’s the major triad,
so-called because it consists of three notes (scale degrees 1, 3, and 5) of the
major scale. Specifically, it’s the C major triad or C major chord.

This simple triad forms the basis of all harmony in the Western
tonal system.

When you hear a major triad, your brain
interprets it as a single, unified sound, even though the chord consists of
three different pitches played or sung simultaneously. The phenomenon of a
unified “chord” sound is analogous to the unified “tone” sound you hear when
someone plucks or plays a single note (Table 34).

TABLE 34 Comparing the Properties of a Single
Tone with the Properties of a Chord (Major or Minor
Triad)

A Single Tone ...

A Chord (Major or Minor

Triad) ...

Consists of a fundamental
tone plus a series of
overtones at higher
pitches.

Although you don’t hear the notes as separate pitches, your brain nevertheless
recognizes and processes them.

The overtones create “tone color,” which enables you to distinguish the
difference between the sound of, say, a guitar, from the sound of a piano.

Sounded together, the notes of the triad create “harmony,” which imparts a
feeling of color and depth to music.

Without the context of a key, the sound of a tone is “at rest"—no tension.

Without the context of a key, the sound of a triad is balanced and stable—no
tension.

When you think about it, then, a single vibrating string or
membrane contains within it all of the acoustical components of both
melody and harmony:

•It incorporates the same ratios of frequencies that yield all the
major and minor scales of the diatonic order.

•It includes the same scale degree notes, sounded
simultaneously, that correspond to the root and the other
notes of the major triad and other chords.

Once your brain had evolved the circuitry to distinguish simple
ratios of frequencies from each other, it also had the necessary
built-in capability to automatically process intervals, tunes, keys, and
chords.

It was
probably inevitable that at some point in human history musicians would
eventually discover and develop Pythagorean-type scales and associated harmony
that made possible Handel’s “Messiah,” Gershwin’s “Someone To Watch Over Me,” and John
Lennon’s “In My Life.”

Have a look at Table 35 below. When you play a C
major triad, here’s what the music modules in your brain actually pick up and
process (fundamental and strongest overtones):

1.The
“C” fundamental, together with a series of overtones, including C itself
(repeated several times as an overtone), plus the notes E and G.

2.The
“E” fundamental, together with a series of overtones, including E itself
(repeated several times as an overtone), plus the notes G♯, and B.

3.The
“G” fundamental, together with a series of overtones, including G itself
(repeated several times as an overtone), plus the notes B, D, and other
overtones.

TABLE 35 Fundamental and First Five Overtones of
C Major Triad

Tone /

Overtone

Multiple of

Funda-mental

Freq.

Ratio

Associated

Scale

Degree

C Major
Triad

C

E

G

Fundamental

1st Overtone

2nd Overtone

3rd Overtone

4th Overtone

5th Overtone

1 (f)

f x 2

f x 3

f x 4

f x 5

f x 6

1 : 1

1 : 2

2 : 3

1 : 2

4 : 5

2 : 3

1

1

5

1

3

5

C

C

G

C

E

G

E

E

B

E

G♯

B

G

G

D

G

B

D

•In
the “C” column, you can see that all three notes of the C major triad (C, E, and
G) appear as overtones of the single C tone.

•In
the “C” and “G” columns, both the E tone and the G tone of the C major chord add
the overtone corresponding to scale degree 7 (the note B). This is the scale
degree associated with the semitone interval that “points” strongly at C (scale
degree 1): the leading tone.

•Other
overtones include D, which also points strongly at C, and G♯, which seeks to
resolve to G (scale degree 5).

So, when you play the notes C, E, and G simultaneously on your
guitar or piano (forming a chord, a major triad), all of the overtones
common to the three tones reinforce each other. This is the
acoustical phenomenon called resonance, discussed in the section
of Chapter 3 on musical instruments and how they work.

The
major triad is a completely balanced, satisfied-sounding chord that doesn’t want
to go anywhere.

More Potential Mixed up Confusion

Chords have roots, whereas scales and keys are centred on
tonic notes.
Do not refer to the first note of a scale as a “scale root”—there’s no such
thing. Scales do not have roots. Chords
have roots.

As you’ll see shortly, a chord is named for its root note. When the root note
of a chord happens to be the same note as the tonic note of a scale, that chord
is called the tonic chord.